As long as someone's playing a wizard (i.e. you) you should be okay. You're the least expendable.
Careful planning is the wizard's bread and butter. Given enough time, he can overcome any obstacle. Sometimes they are completely necessary. Lots of people like them for that. I feel like in most campaigns, time is at a premium, and can cause a problem for those who wait. I know in one group, composed of mostly wizards, a character died because the wizards were hesitant to go rescue her without "enough" spells and rested to regain them and go in "prepared".
Just remember that heroes are heroes, and you get the job done. This game is built that anyone should be able to succeed with good decisions and teamwork, and so any class should contribute if played to its potential.
In your group you have three arcane casters, a divine caster, and a damage dealer. In combat, you should be fine. Summoner and Magus can hold the front line, and you can always summon in more meat for your meatshields. The only thing that your group might need is maybe a party face and/or a skill monkey. Your Summoner should be able to get by with being the face, provided he isn't wearing his monster suit. He could also take care of some skills with Evolution surge: Skilled to get a +8 on any check. So if he is playing his character to its potential, you are good there too. You being a full caster is good, because it opens up more powerful options for your group.